In a 10th century grave in Pskov, a birchbark box was found with a
pair of tortoise brooches and some textiles inside.

The textiles were reconstructed as a tubular suspended skirt and blue
linen chemise.

The exciting bit that made me think of this group, was that Viking
stuff has been mentioned here before, and the people who know about
sarafans can look at it too. (And maybe draw some parallels people
haven't thought of?)